drivers/gpu/drm/vc4/vc4_kms.c

   1 /*
   2  * Copyright (C) 2015 Broadcom
   3  *
   4  * This program is free software; you can redistribute it and/or modify
   5  * it under the terms of the GNU General Public License version 2 as
   6  * published by the Free Software Foundation.
   7  */
   8
   9 /**
  10  * DOC: VC4 KMS
  11  *
  12  * This is the general code for implementing KMS mode setting that
  13  * doesn't clearly associate with any of the other objects (plane,
  14  * crtc, HDMI encoder).
  15  */
  16
  17 #include <drm/drm_crtc.h>
  18 #include <drm/drm_atomic.h>
  19 #include <drm/drm_atomic_helper.h>
  20 #include <drm/drm_crtc_helper.h>
  21 #include <drm/drm_plane_helper.h>
  22 #include <drm/drm_fb_helper.h>
  23 #include <drm/drm_fb_cma_helper.h>
  24 #include <drm/drm_gem_framebuffer_helper.h>
  25 #include "vc4_drv.h"
  26 #include "vc4_regs.h"
  27
  28 struct vc4_ctm_state {
  29         struct drm_private_state base;
  30         struct drm_color_ctm *ctm;
  31         int fifo;
  32 };
  33
  34 static struct vc4_ctm_state *to_vc4_ctm_state(struct drm_private_state *priv)
  35 {
  36         return container_of(priv, struct vc4_ctm_state, base);
  37 }
  38
  39 static struct vc4_ctm_state *vc4_get_ctm_state(struct drm_atomic_state *state,
  40                                                struct drm_private_obj *manager)
  41 {
  42         struct drm_device *dev = state->dev;
  43         struct vc4_dev *vc4 = dev->dev_private;
  44         struct drm_private_state *priv_state;
  45         int ret;
  46
  47         ret = drm_modeset_lock(&vc4->ctm_state_lock, state->acquire_ctx);
  48         if (ret)
  49                 return ERR_PTR(ret);
  50
  51         priv_state = drm_atomic_get_private_obj_state(state, manager);
  52         if (IS_ERR(priv_state))
  53                 return ERR_CAST(priv_state);
  54
  55         return to_vc4_ctm_state(priv_state);
  56 }
  57
  58 static struct drm_private_state *
  59 vc4_ctm_duplicate_state(struct drm_private_obj *obj)
  60 {
  61         struct vc4_ctm_state *state;
  62
  63         state = kmemdup(obj->state, sizeof(*state), GFP_KERNEL);
  64         if (!state)
  65                 return NULL;
  66
  67         __drm_atomic_helper_private_obj_duplicate_state(obj, &state->base);
  68
  69         return &state->base;
  70 }
  71
  72 static void vc4_ctm_destroy_state(struct drm_private_obj *obj,
  73                                   struct drm_private_state *state)
  74 {
  75         struct vc4_ctm_state *ctm_state = to_vc4_ctm_state(state);
  76
  77         kfree(ctm_state);
  78 }
  79
  80 static const struct drm_private_state_funcs vc4_ctm_state_funcs = {
  81         .atomic_duplicate_state = vc4_ctm_duplicate_state,
  82         .atomic_destroy_state = vc4_ctm_destroy_state,
  83 };
  84
  85 /* Converts a DRM S31.32 value to the HW S0.9 format. */
  86 static u16 vc4_ctm_s31_32_to_s0_9(u64 in)
  87 {
  88         u16 r;
  89
  90         /* Sign bit. */
  91         r = in & BIT_ULL(63) ? BIT(9) : 0;
  92
  93         if ((in & GENMASK_ULL(62, 32)) > 0) {
  94                 /* We have zero integer bits so we can only saturate here. */
  95                 r |= GENMASK(8, 0);
  96         } else {
  97                 /* Otherwise take the 9 most important fractional bits. */
  98                 r |= (in >> 23) & GENMASK(8, 0);
  99         }
 100
 101         return r;
 102 }
 103
 104 static void
 105 vc4_ctm_commit(struct vc4_dev *vc4, struct drm_atomic_state *state)
 106 {
 107         struct vc4_ctm_state *ctm_state = to_vc4_ctm_state(vc4->ctm_manager.state);
 108         struct drm_color_ctm *ctm = ctm_state->ctm;
 109
 110         if (ctm_state->fifo) {
 111                 HVS_WRITE(SCALER_OLEDCOEF2,
 112                           VC4_SET_FIELD(vc4_ctm_s31_32_to_s0_9(ctm->matrix[0]),
 113                                         SCALER_OLEDCOEF2_R_TO_R) |
 114                           VC4_SET_FIELD(vc4_ctm_s31_32_to_s0_9(ctm->matrix[3]),
 115                                         SCALER_OLEDCOEF2_R_TO_G) |
 116                           VC4_SET_FIELD(vc4_ctm_s31_32_to_s0_9(ctm->matrix[6]),
 117                                         SCALER_OLEDCOEF2_R_TO_B));
 118                 HVS_WRITE(SCALER_OLEDCOEF1,
 119                           VC4_SET_FIELD(vc4_ctm_s31_32_to_s0_9(ctm->matrix[1]),
 120                                         SCALER_OLEDCOEF1_G_TO_R) |
 121                           VC4_SET_FIELD(vc4_ctm_s31_32_to_s0_9(ctm->matrix[4]),
 122                                         SCALER_OLEDCOEF1_G_TO_G) |
 123                           VC4_SET_FIELD(vc4_ctm_s31_32_to_s0_9(ctm->matrix[7]),
 124                                         SCALER_OLEDCOEF1_G_TO_B));
 125                 HVS_WRITE(SCALER_OLEDCOEF0,
 126                           VC4_SET_FIELD(vc4_ctm_s31_32_to_s0_9(ctm->matrix[2]),
 127                                         SCALER_OLEDCOEF0_B_TO_R) |
 128                           VC4_SET_FIELD(vc4_ctm_s31_32_to_s0_9(ctm->matrix[5]),
 129                                         SCALER_OLEDCOEF0_B_TO_G) |
 130                           VC4_SET_FIELD(vc4_ctm_s31_32_to_s0_9(ctm->matrix[8]),
 131                                         SCALER_OLEDCOEF0_B_TO_B));
 132         }
 133
 134         HVS_WRITE(SCALER_OLEDOFFS,
 135                   VC4_SET_FIELD(ctm_state->fifo, SCALER_OLEDOFFS_DISPFIFO));
 136 }
 137
 138 static void
 139 vc4_atomic_complete_commit(struct drm_atomic_state *state)
 140 {
 141         struct drm_device *dev = state->dev;
 142         struct vc4_dev *vc4 = to_vc4_dev(dev);
 143
 144         drm_atomic_helper_wait_for_fences(dev, state, false);
 145
 146         drm_atomic_helper_wait_for_dependencies(state);
 147
 148         drm_atomic_helper_commit_modeset_disables(dev, state);
 149
 150         vc4_ctm_commit(vc4, state);
 151
 152         drm_atomic_helper_commit_planes(dev, state, 0);
 153
 154         drm_atomic_helper_commit_modeset_enables(dev, state);
 155
 156         /* Make sure that drm_atomic_helper_wait_for_vblanks()
 157          * actually waits for vblank.  If we're doing a full atomic
 158          * modeset (as opposed to a vc4_update_plane() short circuit),
 159          * then we need to wait for scanout to be done with our
 160          * display lists before we free it and potentially reallocate
 161          * and overwrite the dlist memory with a new modeset.
 162          */
 163         state->legacy_cursor_update = false;
 164
 165         drm_atomic_helper_commit_hw_done(state);
 166
 167         drm_atomic_helper_wait_for_vblanks(dev, state);
 168
 169         drm_atomic_helper_cleanup_planes(dev, state);
 170
 171         drm_atomic_helper_commit_cleanup_done(state);
 172
 173         drm_atomic_state_put(state);
 174
 175         up(&vc4->async_modeset);
 176 }
 177
 178 static void commit_work(struct work_struct *work)
 179 {
 180         struct drm_atomic_state *state = container_of(work,
 181                                                       struct drm_atomic_state,
 182                                                       commit_work);
 183         vc4_atomic_complete_commit(state);
 184 }
 185
 186 /**
 187  * vc4_atomic_commit - commit validated state object
 188  * @dev: DRM device
 189  * @state: the driver state object
 190  * @nonblock: nonblocking commit
 191  *
 192  * This function commits a with drm_atomic_helper_check() pre-validated state
 193  * object. This can still fail when e.g. the framebuffer reservation fails. For
 194  * now this doesn't implement asynchronous commits.
 195  *
 196  * RETURNS
 197  * Zero for success or -errno.
 198  */
 199 static int vc4_atomic_commit(struct drm_device *dev,
 200                              struct drm_atomic_state *state,
 201                              bool nonblock)
 202 {
 203         struct vc4_dev *vc4 = to_vc4_dev(dev);
 204         int ret;
 205
 206         if (state->async_update) {
 207                 ret = down_interruptible(&vc4->async_modeset);
 208                 if (ret)
 209                         return ret;
 210
 211                 ret = drm_atomic_helper_prepare_planes(dev, state);
 212                 if (ret) {
 213                         up(&vc4->async_modeset);
 214                         return ret;
 215                 }
 216
 217                 drm_atomic_helper_async_commit(dev, state);
 218
 219                 drm_atomic_helper_cleanup_planes(dev, state);
 220
 221                 up(&vc4->async_modeset);
 222
 223                 return 0;
 224         }
 225
 226         ret = drm_atomic_helper_setup_commit(state, nonblock);
 227         if (ret)
 228                 return ret;
 229
 230         INIT_WORK(&state->commit_work, commit_work);
 231
 232         ret = down_interruptible(&vc4->async_modeset);
 233         if (ret)
 234                 return ret;
 235
 236         ret = drm_atomic_helper_prepare_planes(dev, state);
 237         if (ret) {
 238                 up(&vc4->async_modeset);
 239                 return ret;
 240         }
 241
 242         if (!nonblock) {
 243                 ret = drm_atomic_helper_wait_for_fences(dev, state, true);
 244                 if (ret) {
 245                         drm_atomic_helper_cleanup_planes(dev, state);
 246                         up(&vc4->async_modeset);
 247                         return ret;
 248                 }
 249         }
 250
 251         /*
 252          * This is the point of no return - everything below never fails except
 253          * when the hw goes bonghits. Which means we can commit the new state on
 254          * the software side now.
 255          */
 256
 257         BUG_ON(drm_atomic_helper_swap_state(state, false) < 0);
 258
 259         /*
 260          * Everything below can be run asynchronously without the need to grab
 261          * any modeset locks at all under one condition: It must be guaranteed
 262          * that the asynchronous work has either been cancelled (if the driver
 263          * supports it, which at least requires that the framebuffers get
 264          * cleaned up with drm_atomic_helper_cleanup_planes()) or completed
 265          * before the new state gets committed on the software side with
 266          * drm_atomic_helper_swap_state().
 267          *
 268          * This scheme allows new atomic state updates to be prepared and
 269          * checked in parallel to the asynchronous completion of the previous
 270          * update. Which is important since compositors need to figure out the
 271          * composition of the next frame right after having submitted the
 272          * current layout.
 273          */
 274
 275         drm_atomic_state_get(state);
 276         if (nonblock)
 277                 queue_work(system_unbound_wq, &state->commit_work);
 278         else
 279                 vc4_atomic_complete_commit(state);
 280
 281         return 0;
 282 }
 283
 284 static struct drm_framebuffer *vc4_fb_create(struct drm_device *dev,
 285                                              struct drm_file *file_priv,
 286                                              const struct drm_mode_fb_cmd2 *mode_cmd)
 287 {
 288         struct drm_mode_fb_cmd2 mode_cmd_local;
 289
 290         /* If the user didn't specify a modifier, use the
 291          * vc4_set_tiling_ioctl() state for the BO.
 292          */
 293         if (!(mode_cmd->flags & DRM_MODE_FB_MODIFIERS)) {
 294                 struct drm_gem_object *gem_obj;
 295                 struct vc4_bo *bo;
 296
 297                 gem_obj = drm_gem_object_lookup(file_priv,
 298                                                 mode_cmd->handles[0]);
 299                 if (!gem_obj) {
 300                         DRM_DEBUG("Failed to look up GEM BO %d\n",
 301                                   mode_cmd->handles[0]);
 302                         return ERR_PTR(-ENOENT);
 303                 }
 304                 bo = to_vc4_bo(gem_obj);
 305
 306                 mode_cmd_local = *mode_cmd;
 307
 308                 if (bo->t_format) {
 309                         mode_cmd_local.modifier[0] =
 310                                 DRM_FORMAT_MOD_BROADCOM_VC4_T_TILED;
 311                 } else {
 312                         mode_cmd_local.modifier[0] = DRM_FORMAT_MOD_NONE;
 313                 }
 314
 315                 drm_gem_object_put_unlocked(gem_obj);
 316
 317                 mode_cmd = &mode_cmd_local;
 318         }
 319
 320         return drm_gem_fb_create(dev, file_priv, mode_cmd);
 321 }
 322
 323 /* Our CTM has some peculiar limitations: we can only enable it for one CRTC
 324  * at a time and the HW only supports S0.9 scalars. To account for the latter,
 325  * we don't allow userland to set a CTM that we have no hope of approximating.
 326  */
 327 static int
 328 vc4_ctm_atomic_check(struct drm_device *dev, struct drm_atomic_state *state)
 329 {
 330         struct vc4_dev *vc4 = to_vc4_dev(dev);
 331         struct vc4_ctm_state *ctm_state = NULL;
 332         struct drm_crtc *crtc;
 333         struct drm_crtc_state *old_crtc_state, *new_crtc_state;
 334         struct drm_color_ctm *ctm;
 335         int i;
 336
 337         for_each_oldnew_crtc_in_state(state, crtc, old_crtc_state, new_crtc_state, i) {
 338                 /* CTM is being disabled. */
 339                 if (!new_crtc_state->ctm && old_crtc_state->ctm) {
 340                         ctm_state = vc4_get_ctm_state(state, &vc4->ctm_manager);
 341                         if (IS_ERR(ctm_state))
 342                                 return PTR_ERR(ctm_state);
 343                         ctm_state->fifo = 0;
 344                 }
 345         }
 346
 347         for_each_oldnew_crtc_in_state(state, crtc, old_crtc_state, new_crtc_state, i) {
 348                 if (new_crtc_state->ctm == old_crtc_state->ctm)
 349                         continue;
 350
 351                 if (!ctm_state) {
 352                         ctm_state = vc4_get_ctm_state(state, &vc4->ctm_manager);
 353                         if (IS_ERR(ctm_state))
 354                                 return PTR_ERR(ctm_state);
 355                 }
 356
 357                 /* CTM is being enabled or the matrix changed. */
 358                 if (new_crtc_state->ctm) {
 359                         /* fifo is 1-based since 0 disables CTM. */
 360                         int fifo = to_vc4_crtc(crtc)->channel + 1;
 361
 362                         /* Check userland isn't trying to turn on CTM for more
 363                          * than one CRTC at a time.
 364                          */
 365                         if (ctm_state->fifo && ctm_state->fifo != fifo) {
 366                                 DRM_DEBUG_DRIVER("Too many CTM configured\n");
 367                                 return -EINVAL;
 368                         }
 369
 370                         /* Check we can approximate the specified CTM.
 371                          * We disallow scalars |c| > 1.0 since the HW has
 372                          * no integer bits.
 373                          */
 374                         ctm = new_crtc_state->ctm->data;
 375                         for (i = 0; i < ARRAY_SIZE(ctm->matrix); i++) {
 376                                 u64 val = ctm->matrix[i];
 377
 378                                 val &= ~BIT_ULL(63);
 379                                 if (val > BIT_ULL(32))
 380                                         return -EINVAL;
 381                         }
 382
 383                         ctm_state->fifo = fifo;
 384                         ctm_state->ctm = ctm;
 385                 }
 386         }
 387
 388         return 0;
 389 }
 390
 391 static int
 392 vc4_atomic_check(struct drm_device *dev, struct drm_atomic_state *state)
 393 {
 394         int ret;
 395
 396         ret = vc4_ctm_atomic_check(dev, state);
 397         if (ret < 0)
 398                 return ret;
 399
 400         return drm_atomic_helper_check(dev, state);
 401 }
 402
 403 static const struct drm_mode_config_funcs vc4_mode_funcs = {
 404         .output_poll_changed = drm_fb_helper_output_poll_changed,
 405         .atomic_check = vc4_atomic_check,
 406         .atomic_commit = vc4_atomic_commit,
 407         .fb_create = vc4_fb_create,
 408 };
 409
 410 int vc4_kms_load(struct drm_device *dev)
 411 {
 412         struct vc4_dev *vc4 = to_vc4_dev(dev);
 413         struct vc4_ctm_state *ctm_state;
 414         int ret;
 415
 416         sema_init(&vc4->async_modeset, 1);
 417
 418         /* Set support for vblank irq fast disable, before drm_vblank_init() */
 419         dev->vblank_disable_immediate = true;
 420
 421         ret = drm_vblank_init(dev, dev->mode_config.num_crtc);
 422         if (ret < 0) {
 423                 dev_err(dev->dev, "failed to initialize vblank\n");
 424                 return ret;
 425         }
 426
 427         dev->mode_config.max_width = 2048;
 428         dev->mode_config.max_height = 2048;
 429         dev->mode_config.funcs = &vc4_mode_funcs;
 430         dev->mode_config.preferred_depth = 24;
 431         dev->mode_config.async_page_flip = true;
 432         dev->mode_config.allow_fb_modifiers = true;
 433
 434         drm_modeset_lock_init(&vc4->ctm_state_lock);
 435
 436         ctm_state = kzalloc(sizeof(*ctm_state), GFP_KERNEL);
 437         if (!ctm_state)
 438                 return -ENOMEM;
 439         drm_atomic_private_obj_init(&vc4->ctm_manager, &ctm_state->base,
 440                                     &vc4_ctm_state_funcs);
 441
 442         drm_mode_config_reset(dev);
 443
 444         if (dev->mode_config.num_connector)
 445                 drm_fb_cma_fbdev_init(dev, 32, 0);
 446
 447         drm_kms_helper_poll_init(dev);
 448
 449         return 0;
 450 }